diff --git a/src/systems/log/LogRecord.cc b/src/systems/log/LogRecord.cc
index 8018b402c1..ddff8887bf 100644
--- a/src/systems/log/LogRecord.cc
+++ b/src/systems/log/LogRecord.cc
@@ -62,6 +62,7 @@
 #include "ignition/gazebo/Util.hh"
 
 using namespace ignition;
+using namespace ignition::gazebo;
 using namespace ignition::gazebo::systems;
 
 // Private data class.
diff --git a/src/systems/physics/Physics.cc b/src/systems/physics/Physics.cc
index 84b5276e31..e8f52800d2 100644
--- a/src/systems/physics/Physics.cc
+++ b/src/systems/physics/Physics.cc
@@ -98,6 +98,7 @@
 #include "ignition/gazebo/components/World.hh"
 
 using namespace ignition;
+using namespace ignition::gazebo;
 using namespace ignition::gazebo::systems;
 namespace components = ignition::gazebo::components;
 
diff --git a/test/plugins/Null.cc b/test/plugins/Null.cc
index eabb02dba5..856edcfb5d 100644
--- a/test/plugins/Null.cc
+++ b/test/plugins/Null.cc
@@ -18,6 +18,7 @@
 #include <ignition/gazebo/Entity.hh>
 #include <ignition/plugin/Register.hh>
 
+using namespace ignition::gazebo;
 using namespace ignition::gazebo::systems;
 
 //////////////////////////////////////////////////